Roaming symbol feature for a game of chance

ABSTRACT

A game of chance is conducted on a video gaming machine controlled by a processor in response to a wager. The game includes a plurality of symbols randomly selected for placement in respective symbol positions of a displayed symbol array. A roaming symbol feature is triggered in response to the displayed symbols including a predetermined number of value-based symbols. Each value-based symbol is moved from a respective current symbol position to one or more respective target symbol positions. Payout indicia is revealed for each value-based symbol at the one or more respective target symbol positions. The player is awarded an award based on the payout indicia.

FIELD OF THE INVENTION

[0001] The present invention relates generally to games of chance conducted on gaming machines and, more particularly, to a roaming symbol feature for a game of chance.

BACKGROUND OF THE INVENTION

[0002] Gaming machines, such as slot machines, video poker machines and the like, have been a cornerstone of the gaming industry for several years. Generally, the popularity of such machines with players is dependent on the likelihood (or perceived likelihood) of winning money at the machine and the intrinsic entertainment value of the machine relative to other available gaming options. Where the available gaming options include a number of competing machines and the expectation of winning each machine is roughly the same (or believed to be the same), players are most likely to be attracted to the most entertaining and exciting of the machines. Shrewd operators consequently strive to employ the most entertaining and exciting machines available because such machines attract frequent play and hence increase profitability to the operator. Accordingly, in the competitive gaming machine industry, there is a continuing need for gaming machine manufacturers to produce new types of games, or enhancements to existing games, which will attract frequent play by enhancing the entertainment value and excitement associated with the game.

[0003] One concept that has been successfully employed to enhance the entertainment value of a game is the concept of a “secondary” or “bonus” game that may be played in conjunction with a “basic” game. The bonus game may comprise any type of game, either similar to or completely different from the basic game, which is entered upon the occurrence of a selected event or outcome of the basic game. Because the bonus game concept offers tremendous advantages in player appeal and excitement relative to other known games, and because such games are attractive to both players and operators, there is a continuing need to develop new features and themes for bonus games to satisfy the demands of players and operators. Preferably, such new bonus game features and themes will maintain, or even further enhance, the level of player excitement offered by bonus games heretofore known in the art. The present invention is directed to satisfying these needs.

SUMMARY OF THE INVENTION

[0004] A game of chance is conducted on a video gaming machine controlled by a processor in response to a wager. The game includes a plurality of symbols randomly selected for placement in respective symbol positions of a displayed symbol array. A roaming symbol feature is triggered in response to the displayed symbols including a predetermined number of value-based symbols. Each value-based symbol is moved from a respective current symbol position to one or more respective target symbol positions. Payout indicia is revealed for each value-based symbol at the one or more respective target symbol positions. The player is awarded an award based on the payout indicia.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The foregoing and other advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:

[0006]FIG. 1 is a perspective view of a gaming machine embodying the present invention;

[0007]FIG. 2 is a block diagram of a control system suitable for operating the gaming machine;

[0008]FIG. 3 is a display screen capture associated with a basic slot game and showing a symbol combination for triggering a first roaming symbol feature;

[0009]FIGS. 4 and 5 are display screen captures associated with the first roaming symbol feature;

[0010]FIG. 6 is a display screen capture associated with the basic slot game and showing a symbol combination for triggering a second roaming symbol feature; and

[0011]FIGS. 7, 8, and 9 are display screen captures associated with the second roaming symbol feature.

[0012] While the invention is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

DESCRIPTION OF SPECIFIC EMBODIMENTS

[0013] Turning now to the drawings and referring initially to FIG. 1, a gaming machine 10 is operable to play a game of chance having a sky scenery theme. The game of chance features a basic slot game with five simulated spinning reels and a pair of roaming symbol features triggered by respective start-feature outcomes in the basic slot game. In addition to the roaming symbol features, the basic slot game may produce certain outcomes for triggering other special features and bonus games. The gaming machine 10 includes a visual display 12 preferably in the form of a dot matrix, CRT, LED, LCD, electro-luminescent, or other type of video display known in the art. The display 12 preferably includes a touch screen overlaying the monitor. In the illustrated embodiment, the gaming machine 10 is an “upright” version in which the display 12 is oriented vertically relative to the player. Alternatively, the gaming machine may be a “slant-top” version in which the display 12 is slanted at about a thirty-degree angle toward the player of the gaming machine 10.

[0014]FIG. 2 is a block diagram of a control system suitable for operating the gaming machine 10. Money/credit detector 16 signals a central processing unit (“CPU”) 18 when a player has inserted money or played a number of credits. The money may be provided by coins, bills, tickets, coupons, cards, etc. Then, the CPU 18 operates to execute a game program that causes the display 12 to display five simulated symbol-bearing reels. The player may select a number of pay lines to play, an amount to wager, and start game play via the touch screen 20 or the push-buttons 14, causing the CPU 18 to set the reels in motion, randomly select a game outcome, and then stop the reels to display symbols corresponding to the pre-selected game outcome. In one embodiment, two of the basic game outcomes trigger respective roaming symbol features.

[0015] A system memory 22 stores control software, operational instructions and data associated with the gaming machine 10. In one embodiment, the system memory 22 comprises a separate read-only memory (ROM) and battery-backed random-access memory (RAM). However, it will be appreciated that the system memory 22 may be implemented on any of several alternative types of memory structures or may be implemented on a single memory structure. A payoff mechanism 24 is operable in response to instructions from the CPU 18 to award a payoff to the player in response to certain winning outcomes that might occur in the basic game or the roaming symbol features. The payoff may be provided in the form of coins, bills, tickets, coupons, cards, etc. The payoff amounts are determined by one or more pay tables stored in the system memory 22.

[0016] Referring to FIG. 3, the basic game is implemented on the display 12 on five video simulated spinning reels 30-34 with nine pay lines 40-48. Each of the pay lines 40-48 extends through one symbol on each of the five reels 30-34. Generally, game play is initiated by inserting money or playing a number of credits, causing the CPU to activate a number of pay lines corresponding to the amount of money or number of credits played. In one embodiment, the player selects the number of pay lines (between one and nine) to play by pressing a “Select Lines” key 50 on the video display 12. The player then chooses the number of coins or credits to bet on the selected pay lines by pressing the “Bet Per Line” key 52.

[0017] After activation of the pay lines, the reels 30-34 may be set in motion by touching the “Spin Reels” key 54 or, if the player wishes to bet the maximum amount per line, by using the “Max Bet Spin” key 56 on the video display 12. Alternatively, other mechanisms such as, for example, a lever or push button may be used to set the reels in motion. The CPU uses a random number generator to select a game outcome (e.g., “basic” game outcome) corresponding to a particular set of reel “stop positions.” The CPU then causes each of the video reels 30-34 to stop at the appropriate stop position. Video symbols are displayed on the reels 30-34 to graphically illustrate the reel stop positions and indicate whether the stop positions of the reels represent a winning game outcome.

[0018] Winning basic game outcomes (e.g., symbol combinations resulting in payment of coins or credits) are identifiable to the player by a pay table. In one embodiment, the pay table is affixed to the machine 10 and/or displayed by the video display 12 in response to a command by the player (e.g., by pressing the “Pay Table” button 58). A winning basic game outcome occurs when the symbols appearing on the reels 30-34 along an active pay line correspond to one of the winning combinations on the pay table. A winning combination, for example, could be three or more matching symbols along an active pay line, where the award is greater as the number of matching symbols along the active pay line increases. If the displayed symbols stop in a winning combination, the game credits the player an amount corresponding to the award in the pay table for that combination multiplied by the amount of credits bet on the winning pay line. The player may collect the amount of accumulated credits by pressing the “Collect” button 59. In one implementation, the winning combinations start from the first reel 30 (left to right) and span adjacent reels. In an alternative implementation, the winning combinations start from either the first reel 30 (left to right) or the fifth reel 34 (right to left) and span adjacent reels.

[0019] Included among the plurality of basic game outcomes are a pair of start-feature outcomes for triggering play of respective roaming symbol features. A start-feature outcome may be defined in any number of ways. For example, a start-feature outcome occurs when a special start-feature symbol or a special combination of symbols appears on one or more of the reels 30-34. The start-feature outcome may require the combination of symbols to appear along an active pay line, or may alternatively require that the combination of symbols appear anywhere on the display regardless of whether the symbols are along an active pay line. The appearance of a start-feature outcome causes the CPU to shift operation from the basic game to the respective roaming symbol feature of the present invention.

[0020] In the embodiment illustrated in FIG. 3, a SUN symbol 60 on reel 30 and a MOON symbol 62 on reel 34 triggers a first roaming symbol feature called an eclipse bonus. In response to triggering the eclipse bonus, either the MOON symbol 62 moves toward the SUN symbol 60 or the SUN symbol 60 moves toward the MOON symbol 62. If the background to the symbol array represents daytime as illustrated, the MOON symbol 62 moves in a random path from its initial symbol position on reel 34 to the symbol position of the SUN symbol 60 on reel 30. If, however, the background to the symbol array represents night time (not shown), the SUN symbol 60 moves in a random path from its initial symbol position on reel 30 to the symbol position of the MOON symbol 62 on reel 34.

[0021] Whichever symbol moves, the symbol progressively moves vertically or horizontally, but preferably not diagonally, between adjacent symbol positions until reaching the final symbol position on the farthest reel. The moving symbol always appears to be moving toward the final symbol position on the farthest reel such that it preferably never re-crosses its path and never returns to a reel from which it has already departed. As the moving symbol crosses different symbol positions in its movement, each crossed symbol position may be highlighted and reveals an associated multiplier to be applied to the initial total wager.

[0022] In the example illustrated in FIGS. 4 and 5, the MOON symbol 62 progressively moves in a random path from the bottom symbol position on reel 34 to the top symbol position on reel 30. The random path takes the MOON symbol 62 across the bottom symbol position on reel 33, the middle symbol position on reel 33, the middle symbol position on reel 32, the top symbol position on reel 32, the top symbol position on reel 31, and finally the top symbol position on reel 30. The symbol positions along this random path reveal the respective multipliers 2×, 5×, 3×, 4×, and 2×. At the completion of the eclipse bonus, the player is awarded a bonus equal to the initial total wager multiplied by the sum of the revealed multipliers (e.g., 9×(2+5+3+4+2)=144 credits). The CPU then shifts operation back to the basic slot game.

[0023] Referring to FIG. 6, a second roaming symbol feature called a balloon bonus is triggered by three or more BALLOON symbols 66, 68, and 70 appearing anywhere on the stopped reels following a reel spin. In response to triggering the balloon bonus, the BALLOON symbols progressively rise on their respective reels until reaching the top symbol positions of their respective reels. Alternatively, if preferred by the game designer, the BALLOON symbols may rise above their respective reels, completely leaving the symbol array. As each BALLOON symbol crosses different symbol positions in its movement, each crossed symbol position may be highlighted and reveals an associated multiplier to be applied to the initial total wager. The multiplier preferably increases for each successive symbol position crossed by the BALLOON symbol.

[0024] For example, the starting symbol position of a BALLOON symbol on a reel may be worth a multiplier of 1×, and this multiplier may increase by 2× for each successive symbol position crossed by the BALLOON symbol. Therefore, a BALLOON symbol such as the symbol 68 in FIGS. 7-9 starting from a bottom symbol position on reel 32 would yield a final multiplier of 5× as it progressively rises from the bottom symbol position worth 1×, through the middle symbol position worth an additional 2×, and to the top symbol position worth an additional 2×. A BALLOON symbol such as the symbol 66 in FIGS. 7-9 starting from a middle symbol position on reel 30 would yield a final multiplier of 3× as it rises from the middle symbol position worth 1× to the top symbol position worth an additional 2×. A BALLOON symbol such as the symbol 70 in FIGS. 7-9 starting from a top symbol position on reel 34 would yield a final multiplier of 1× as it rises from the top symbol position worth 1×.

[0025] The current multiplier associated with a BALLOON symbol is superimposed over the BALLOON symbol as it rises on its respective reel. When the BALLOON symbol rises to the top symbol position of its respective reel, the final multiplier for that BALLOON symbol is revealed. At the completion of the balloon bonus, the player is awarded a bonus equal to the initial total wager multiplied by the sum of the final multipliers for each BALLOON symbol (e.g., 9×(3+5+1)=81 credits). The CPU then shifts operation back to the basic slot game.

[0026] In a preferred embodiment, any BALLOON symbol(s) starting from a bottom symbol position begins to rise first while other BALLOON symbols remain stationary. When the rising BALLOON symbol(s) reaches a middle symbol position, any BALLOON symbol(s) starting from a middle symbol position begins to rise along with the BALLOON symbol(s) that started from the bottom symbol position. Finally, when the rising BALLOON symbols reach a top symbol position, any BALLOON symbol(s) starting from a top symbol position begins to rise along with the BALLOON symbols that started from the bottom and middle symbol positions.

[0027] While the present invention has been described with reference to one or more particular embodiments, those skilled in the art will recognize that many changes may be made thereto without departing from the spirit and scope of the present invention. For example, the roaming symbol feature may be modified so that the roaming symbol moves in any direction, including horizontally, vertically, or diagonally, and is not limited to movement between adjacent symbol positions. The appearance of the symbol itself may be modified such that movement of the symbol is consistent with the type of symbol being moved. Also, the roaming symbols may yield credit amounts instead of multipliers as the symbols cross different symbol positions. Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims. 

What is claimed is:
 1. A method of conducting a game of chance on a gaming machine controlled by a processor, comprising: receiving a wager from a player; displaying a symbol array including a plurality of symbol positions, the plurality of symbol positions containing respective symbols, the symbols including a predetermined number of value-based symbols; moving each value-based symbol from a respective current symbol position to one or more respective target symbol positions; revealing payout indicia for each value-based symbol at the one or more respective target symbol positions; and awarding an award based on the payout indicia to the player.
 2. The method of claim 1, wherein the payout indicia is a multiplier, the award being equal to the wager multiplied by a sum of each revealed multiplier.
 3. The method of claim 1, wherein the predetermined number of value-based symbols is greater than one.
 4. The method of claim 3, wherein the symbol array includes a plurality of rows and columns, and wherein the step of moving each value-based symbol includes moving each value-based symbol along a respective column.
 5. The method of claim 4, wherein the payout indicia for each value-based symbol increases in value as the value-based symbol moves to successive ones of the one or more target symbol positions in its respective column.
 6. The method of claim 1, wherein the predetermined number of value-based symbols is one.
 7. The method of claim 6, wherein the symbol array includes a plurality of rows and columns, and wherein the step of moving each value-based symbol includes moving the value-based symbol in a random path across the symbol array from a first of the columns to a last of the columns.
 8. A method of conducting a game of chance on a gaming machine controlled by a processor, comprising: receiving a wager from a player; randomly selecting symbols for placement in respective symbol positions of a displayed symbol array; triggering a roaming symbol feature in response to the displayed symbols including a predetermined number of value-based symbols; moving each value-based symbol from a respective current symbol position to one or more respective target symbol positions; revealing payout indicia for each value-based symbol at the one or more respective target symbol positions; and awarding an award based on the payout indicia to the player.
 9. The method of claim 8, wherein the payout indicia is a multiplier, the award being equal to the wager multiplied by a sum of each revealed multiplier.
 10. The method of claim 8, wherein the predetermined number of value-based symbols is greater than one.
 11. The method of claim 10, wherein the symbol array includes a plurality of rows and columns, and wherein the step of moving each value-based symbol includes moving each value-based symbol along a respective column.
 12. The method of claim 11, wherein the payout indicia for each value-based symbol increases in value as the value-based symbol moves to successive ones of the one or more target symbol positions in its respective column.
 13. The method of claim 8, wherein the predetermined number of value-based symbols is one.
 14. The method of claim 13, wherein the symbol array includes a plurality of rows and columns, and wherein the step of moving each value-based symbol includes moving the value-based symbol in a random path across the symbol array from a first of the columns to a last of the columns.
 15. A game of chance for a video gaming machine controlled by a processor in response to a wager, comprising: means for displaying a symbol array including a plurality of symbol positions, the plurality of symbol positions containing respective symbols, the symbols including a predetermined number of value-based symbols; means for moving each value-based symbol from a respective current symbol position to one or more respective target symbol positions; means for revealing payout indicia for each value-based symbol at the one or more respective target symbol positions; and means for awarding an award based on the payout indicia to the player.
 16. A game of chance for a video gaming machine controlled by a processor in response to a wager, comprising: means for randomly selecting symbols for placement in respective symbol positions of a displayed symbol array; means for triggering a roaming symbol feature in response to the displayed symbols including a predetermined number of value-based symbols; means for moving each value-based symbol from a respective current symbol position to one or more respective target symbol positions; means for revealing payout indicia for each value-based symbol at the one or more respective target symbol positions; and means for awarding an award based on the payout indicia to the player. 